I have been planning on installing DPs on my 335xi for the last several weeks. Due to my location, it would have to be a DIY job. I studied the BMW TIS and Bentley manual, and acquired necessary tools.

Things went fairly smoothly until the actual removal of the DPs (see below for full description). If anybody has advice on how to get beyond this step, then I can put together a DIY for this project.

As recommended by the BMW TIS and Bentley, I did the following:

1. Removed passenger side axle/CV

2. Removed bearing pedestal

3. Disconnected O2 sensors

4. Unclamped stock DPs at wastegates

5. Unclamped stock DPs from hanger/bracket

6. Unclamped stock DPs from catback

Initially this seemed to provide enough room to negotiate the stock DPs around the subframe. I was trying to remove the front turbo DP (cylinder 1-3) first as the rear turbo DP is totally hidden behind the front DP.

To my total irritation, I could not get the front DP out. I tried pulling the DP straight down (where the bearing pedestal normally would be). I also tried rotating it outwards (where the CV and steering knuckle are normally located).

No matter what I did, the back end of the DP (where it joins with the catback) could not clear the crossmember (that is part of the subframe. This was cut by a member who I think later came to regret it).

At this point there are only four options left:

1. Remove small heat shield attached to the back right corner of subframe. This would be difficult as one of the screws is very difficult to access, and I'm doubtful this will provide enough room to make a difference.

2. Loosen steering rack as is done for installing DPs on RWD models. I don't think this will work since you can't slide the steering rack forward as it would bump into the subframe.

3. Drop subframe about 2 inches. Doable, but a giant PITA.

4. Cut the stock DPs. Don't want to do this since I want the option of reinstalling stock DPs at later date.